Small Engine, Big Efficiency? Why Bigger Can Be Better.

Small Engine, Big Efficiency? Why Bigger Can Be Better.

Or,

How to NOT waste your used car budget on something you'll hate.

As mentioned last post I've been crunching date looking to get the most out of my budget for my next car. While there are any number of tasty rides available for under 3k - I was looking about 6 months ago back when a lady was telling me she'd help me buy a 'cleaner' ride than my Benz Diesel, as she was apparently Compression Ignition Phobic - most of the truly cool ones are either too small (got a dog and crap, need space), too expensive to keep up, or too fuel thirsty. Some are all three.

Some, like the Family Truckster here, only come in
Metallic Pea.

BTW, real Craigslist find while on my search..

It started out years ago when I started looking for a 'fuel efficient midsize SUV'. I looked at various 4 cylinder models - Isuzu Troopers and the like - and came to a conclusion - mostly all a four offered at that level was less power than a six. While there were some fuel efficiency gains, we're still talking dismal mileage.

So how does one avoid having four cylinder passing power with eight cylinder mileage?

I've been using www.fueleconomy.gov extensively lately, and I can't recommend it enough for those of you buying a new or used car. Like a lot of people I hear 'four cylinder' and immediately think two things: 'low power' and '30mpg' or something along those lines. Sadly, though, there are a LOT of four cylinder cars and trucks out there that, depending on your driving style and whether you're mostly a city or highway driver, might not only be slower than your current ride, or the 'ride you want', but less efficient and economical as well. Not to mention, less capable...

For instance, last year I was getting a little bit of an 'enthusiast sales pitch' from a guy who likes the Toyota Previa minivans. They're pretty cool for what they are, bland styling for sure (I remember thinking of them as 'eggs on wheels' in junior high), but I was looking at something that would absolutely blend into modern traffic but be old enough to be cheap. Huge amount of room for music gear and/or living space. I saw a 2.2l Toyota four specified and thought it was a good match - it HAD to get better mileage than my 2 ton plus 5.7l V8 Buick, right?

Well, kinda. 

As you can see here, (http://fueleconomy.gov/feg/Find.do?action=sbs&id=11063&id=11404&id=27947&id=11432) the Previa gets 17 city mpg, 21 highway,  for a combined 18 mpg. 

The Roadie got 15mpg city, 23 highway, and 18 combined.

So if you had a 50/50 mix of highway and city driving the result is a wash. Go with what moves you - for me, that was 5.7 liters of roaring tailpipe music in a car that literally got me mistaken for a pimp - by a real pimp. 

If you're mostly driving in town, the Previa has a 2mpg edge, and if you're driving mostly highway, the same 2mpg edge goes to the Buick.

If I could easily swallow the monetary difference, the Previa looks outmatched by quite a bit. Would keep me from going bonkers thinking about engine swaps, though, because the Previa is pretty much foolproof in that regard - the factory that built it decided it was just easier to supercharge the stock motor. Makes a shadetree guy like me think of greener pastures...

You'd think a 5.7l, 260+hp American OHV V8 and a 2.2l DOHC Japanese I-4 would get wildly different results in the mileage department. I think it's best expressed as 'Overall Efficiency - Work Demanded = Actual Efficiency'. If the four didn't have to work so hard to move those 3500lbs of van, it would get better mileage. The V8 can lope around at lower rpm and do the same work in a relaxed manner. I don't doubt the LT1 would probably match or better the stock 2.2l powerplant if a swap were possible - after all, while the aerodynamics might suffer a bit, the Previa is 700lbs lighter too.

Reminds me of the old C5 Z06 vs BMW M3 reviews. I recall that the NA I-6 of the BMW put out less torque at peak than the LS6 did - at idle. Remember, torque = work, and out of horsepower or torque, the latter is the only one directly measured, rather than extrapolated by a formula (torque x RPM/5252 = HP). The less you have available, the higher the motor has to spin, and the more fuel consumed. 

Pictured: Efficiency. No, seriously...stop laughing!

It's a path to fast, and a path to efficient, apparently. Comparing more apples to apples motors, in a way, I recently got into a bit of a spat on YouTube with a Lexus fan dissing GM cars. Looking up the LFA specs, I noted that not only does the 3300lb, 550hp V10 'supercar' barely beat the ZL1 Camaro around the Nordschlieffe by 3 seconds over 13 miles, the 6.2l, Supercharged, 638hp LS9 in the ZR1 get's better mileage than the 550hp 4.8l Lexus V10. Not by a few, either - a base 6.2l Vette will turn in city mpg similar to the LFA's hwy mpg. 

Overall, the 'huge' engines, 6.2l, 7.0l, and 6.2SC, all turned in better mileage by about 5mpg average. 

(Vette Lineup VS Lexus LFA MPGs here - http://www.fueleconomy.gov/feg/Find.do?action=sbs&id=31326&id=31328&id=31327&id=31089. Left to Right - 'Base' Vette, Z06, ZR1, LFA)

Not bad considering the ZR1 is a third of the price of the 'base' LFA. Not a bad comparision, either, as both cars are obviously designed with high performance in mind and have similar curb weights. Drag coefficients are as follows: 'Base' Vette, 0.28, Z06 0.34, ZR1 0.36, and LFA 0.31. Even the 'porky' Camaro ZL1's average MPG is 16 - which is the LFA's highway rating. That's with a .35 cD and an extra 700 lbs or so to push around. (http://fueleconomy.gov/feg/Find.do?action=sbs&id=32161&id=31089)

Looks like a lot of engineering misapplied in a vain attempt to give a 'halo' effect to a bland product line. Or an example of how low end torque can be used for work, play, AND efficiency - but that's no news to diesel heads. 

Pictured: $375k worth of slower than a Vette and less
MPG than a Supercharged 6.2l Camaro.

Also pictured - why 'Hot Rod Black' should only applied to,
you know, hot rods.

But it also illustrates that, down here in the real world, not everything is cut and dried as it seems. 'Smaller motor = more efficiency' doesn't always compute. Not that one should just as blindly buy any old V8 engine and assume it'll be efficient for your particular use, either. 

So, for instance, if I were to truly put down roots here in Venice and want to stay, a Previa makes slightly better sense - who gets to cruise in overdrive in LA during anything but the wee morning hours? Almost entirely used in the city, over 10k miles, the Buick would consume 666 gallons (hee!) and the Previa only 588, a difference of 78 gallons and 351 dollars in a typical owner's year. That's about 30 bucks a month. Of course the same 2mpg difference in an all highway scenario would be the same, and for someone who could care less about the 30 bucks a month, well, I've got plenty of blog space devoted to the big B body. 

But, as I'm planning on going to New Orleans soon and have 2000 miles or so of highway driving, a Roadie would actually save me gas money, as well as being the cooler ride. When I lived in the Desert and you'd be in overdrive by the time you passed your neighbor's house, there would be no question - more power AND more MPG, please, all in a ride fit for a prince - or, at least, a pimp from Pomona...

Ok, so mine wasn't Magenta. Otherwise, I was a little embarrassed...

Oh, and I don't do decals, so NYAAH.

(From 'Bloom County' comic strip, published June 15th 1982)

Comparisons like this illustrate the finer details of choosing a ride, especially on a pretty limited budget. I, personally, wouldn't want to pay more or the same amount to get less of what I want out of my purchase. 

So at the time I also compared the Chevy Astro 2wd passenger van, a solid workhorse that's become practically legion as you literally see them all the time in LA. And I considered another Mercedes 300D Turbo in a pursuit of efficiency. Both were being weighed against the Previa and Roadmaster.

The Astro, despite a similar curb weight, almost identical transmission, and a 4.3l V6, gets worse mileage than the Buick. Without going into all the other reasons, this shit-canned the Astro pretty quickly in my eyes, though I'd consider one as a secondary vehicle. To be fair, the parts availability of the Astro is great (it's all S10/G Body parts and other standard GM RWD stuff), the Previa will never take to engine swaps, and Toyota's solution to having adequate power in a Previa, the S/C supercharged model, turns in similar MPG to an Astro. The Astro, however, would take to any number of engine swaps in search of more power or economy.

FWIW, the differences between the 4.3l V6 Astro, especially in MPFI trim (190hp, 260lb-ft), and the Previa LE S/C (160hp, 200lb-ft), considering the 1mpg difference city/hwy, are pretty much obvious. A low production high tech engine that was only made for one generation (plus the funky configuration, accessory drive, etc) vs. a 6 cylinder version of the venerated SBC in production for two decades -  are semi negligible - until one gets to the tow rating. The Astro? 5500lbs, same as the Roadie. The Previa? 3600lbs. If you want to tow, you know where to look. If goofy, one-time only arrangements and 'mid engine' minivans are your thing, well, best of luck with that. 

The Mercedes W123 body 300D was an interesting story as it's a 21mpg city, 23hwy, 22 combined car. So I'd gain quite a bit in town - more than most cars in the price segment that aren't 4 cylinder compacts with sub 2.0l engines - but no more highway mpg than my Buick. The city mpg was where I wasn't happy, and in that regard the 300D had better 'city manners', such as parking (GREAT turn radius/steering angle) and creamed the Big Bad Buford by 6mpg in the city. But... 

Then the gear head came into play.

"You know, the LT1 in the Buick's already been breathed on a bit, should be 285hp or more, probably stockish 330lb ft. The OM617a in the 300D has a mere 123hp and 170lb-ft, and while it can make more, it's a 2500 dollar Myna pump and a serious turbo upgrade away from any impressive numbers..."

Plus, yeah, I'm trading THIS for a Previa? Riiiight.....

That sealed it. I kept the Buick for another year after this initial run down. I still kind of regret selling it, to be honest - the car was a bonafide G-ride, and even a local character - an Inuit orphan who we all know as 'Pirate Darren' due to his ever-present leather Tri-Corner Hat, aka one of the least 'gangster' people I know - called my ride 'Gangster As Fuck'. Hard to show up a few days later in a car that looks like I knocked up a broad after hearing that a few dozen times...

So I kept the Buick for another year. I don't regret it, in a car guy way, in a 'practical guy' way I kinda do though. Really, the better option than both was the 300D and it's probably going to be my next ride, as these Benz built-to-a-standard-not-a-price-point tanks are still, in my opinion, the automotive deal of the century, and the 300D's average mpg is Accord/Altima like (http://fueleconomy.gov/feg/Find.do?action=sbs&id=27947&id=11108&id=11827), but I don't have to drive a frumpy mid 90's midsize FWD sedan. Granted, they're faster, and rated at better mpgs highway. But the 300D also has been reported reliably to get upper 20s highway if you're not driving 80 the whole way, too. 

Something to be said about getting into a Benz for the same price as an Accord and getting similar affordability and efficiency. Not to mention, this:

Choose wisely.